Headphones and headsets are used for hearing protection and for communication in a variety of industrial settings. As used and defined herein, the terms “headset” and headphone” are used interchangeably to refer to devices that engage a user's ears to provide sound, noise protection, or both for the user.
The human audio frequency band is generally 20 Hz to 20 kHz, however, some frequency sub-bands, such as 63 Hz to 8 kHz within the human audio frequency band are of special interest for hearing protection. Headsets typically include two ear cups edged with a soft material to make a sound-resistant seal between the ear cups and the user's head and a head band adjustably connecting the two ear cups. Headsets that provide both hearing protection and wireless communications are of particular interest, as the communications speaker with external noise penetrating the ear cup can contribute to the total noise dose. OSHA sets standards for hearing protection in high-noise environments, such as factories and flight lines. Headsets are often worn improperly due to user preferences that are at variance with best safety practices. Eyeglass stems, jewelry, or other accessories worn by the user may also impact the effectiveness of the sound-resistant seal. Knowing this, OSHA derates hearing protection devices from the technical capability of the actual hearing protection headset to a lower rating to take improper fit into consideration. Consequently, hearing protection devices must be over-designed and over-constructed to still qualify for use after the derating. Overcompensating for improperly used hearing protection increases costs of providing hearing protection.
U.S. Pat. No. 8,391,503 B2 issued 2013 Mar. 5 to Bayley et al., discloses a system for measuring noise exposure associated with use of a wireless headset. Bayley does not address fit detection. U.S. Pat. No. 6,826,515 B2 issued 2004 Nov. 30 to Bernardi et al. discloses an apparatus for monitoring and controlling exposure to noise related to a headset by changing the gain on the voice input to ensure that total noise does not exceed a threshold. Bernardi does not address fit detection. U.S. Pat. No. 4,625,083 issued 1986 Nov. 25 to Poikela discloses dual microphones, one for speech and one for ambient external noise, for independently processing noise and voice. Poikela does not address fit detection. U.S. Pat. No. 7,978,861 B2 issued 2011 Jul. 12 to Michael discloses A method for continuously monitoring noise exposure level of a person via measuring sound level within an ear canal of the person. Michael does not address fit detection.
Therefore, a need exists for a hearing protection headset that can detect when it is being improperly worn and report this detection at least to the user.